The present invention relates to a compressed air dryer. It finds particular application in conjunction with reducing oil expelled to atmosphere when the air dryer is purged and will be described with particular reference thereto. It will be appreciated, however, that the invention is also amenable to other applications.
The purge exhaust of a compressed air regenerative dryer used on air braked vehicles normally consists of water mixed with some amount of oil. The oil may be introduced into the air dryer from the compressor. The water and oil are expelled from a purge exhaust valve of the air dryer during a purge cycle. For example, the water and oil may be expelled to atmosphere. Exhausting oil to atmosphere is environmentally undesirable. In addition, the oil tends to accumulate over time around the purge exhaust valve. This oil accumulation frequently leads to an incorrect perception that the compressor and/or air dryer is prematurely worn, resulting in unnecessary replacements.
Currently, compressed air condensate management separators, including baffles and coalescing elements, are used to separate oil and emulsions from the condensate water of industrial compressed air systems. However, these separators tend to be bulky, are typically designed for stationary industrial compressed air applications, and are not suitable to be mounted on motor vehicles. Wicks have also been used to transfer oil from a sump volume to an oil collector.
The present invention provides a new apparatus and method for processing purge exhaust.